A wide variety of items are shipped in containers which must be at least partially filled with packing material in order to prevent breakage or damage to such items. One of the most popular forms of packing material is formed of polystyrene or "Styrofoam" fabricated in a generally cylindrical shape, commonly known as a "peanut." In most instances, a layer of Styrofoam peanuts is first placed at the bottom of the container, the item to be shipped is positioned atop such layer and then additional Styrofoam peanuts are introduced into the container along the sides and top of the item to complete the packing operation.
One problem with the use of Styrofoam peanuts as loose fill packing material is that items tend to shift, settle or creep within the container in the course of shipment. It has been found that the Styrofoam peanuts tend to move relative to one another, and, in turn, permit movement of items they surround to the bottom or sides of the shipping container where damage to such items can occur.
This problem of shifting of items within a shipping container has been solved to some extent by the use of other packing materials in addition to or as a replacement for the Styrofoam peanuts. For example, a blow-in foam has been utilized with Styrofoam peanuts to enhance the shock absorbing and encapsulating properties of the packing material, but this adds substantial expense and time to the packing operation. Other packing materials such as "bubble-pack", i.e. sheets of plastic material having encapsulated pockets of air, have also been used as an addition to or substitute for Styrofoam peanuts. Unfortunately, bubble-pack is also expensive and can be difficult to work with depending upon the size, shape and/or weight of an item to be shipped.
Another problem with Styrofoam peanuts and other types of foam packing materials is that they promote the formation of static electricity within the shipping container. The presence of static electricity in packing materials can create substantial problems with sensitive electrical components. Additionally, electrostatically charged foam material tends to attract contaminants and other impurities which make their use in the shipment of food items and similar articles undesirable. Although the development of an electrostatic charge on Styrofoam peanuts and other types of foam packing materials can be reduced by the addition of an antistatic agent, the process of applying an antistatic agent to such packing materials is expensive both in terms of material cost and the labor required to apply the antistatic agent.
Styrofoam peanuts, blow-in foam, bubble-packaging and other types of plastic packing material all create a disposal problem and can be dangerous to the environment. Plastic materials are inert and do not biodegrade when placed in a landfill, and therefore take up a large quantity of space. Additionally, a chemical leaching can take place with certain types of plastics which creates environmental hazards such as pollution of groundwater supplies and other hazards. A number of states currently have legislation pending to reduce or eliminate the dumping of styrofoam products and other types of plastics within sanitary landfills and this could pose a significant disposal problem for companies employing loose fill material of this type or who receive products packaged in such material.